How to Test for Tuberculosis (TB): FAQ Guide

Published February 25, 2025. Last updated March 6th, 2025.

This guide covers key information about how to get tested for TB, from symptoms and risks, to testing options and result interpretation.

Tuberculosis (TB) is an infectious disease that primarily affects the lungs but can also impact other parts of the body. It remains a major global health concern, infecting more than 10 million people annually. While many infected individuals do not develop active TB disease, the World Health Organization reports that TB still causes approximately 1.5 million deaths worldwide each year.¹

In the United States, the Centers for Disease Control and Prevention (CDC) estimates that up to 13 million people have inactive TB, meaning they carry the bacteria but do not experience symptoms.² TB spreads through the air from infected individuals, making timely testing crucial for preventing its spread.

What Are the Symptoms and Risks of Tuberculosis (TB)?

Inactive (latent) TB infections don’t cause symptoms, though they can lead to a positive result on a blood or skin test.³ At the onset of an active TB disease, some people experience flu-like symptoms, such as low fever, tiredness, or cough.⁴

Active TB Disease Symptoms:

• Persistent cough lasting more than two weeks
• Chest pain
• Coughing up blood or mucus
• Fatigue or weakness
• Fever and chills
• Night sweats
• Unexplained weight loss²

Who Is at Higher Risk for TB?

Individuals at higher risk for developing TB include:³

• People with weakened immune systems, including those with HIV, diabetes, or those undergoing cancer treatment
• Frequent travelers or residents of high TB prevalence areas, such as India, China, Indonesia, Nigeria, South Africa, most countries in Latin America, the Caribbean, Africa, Asia, Eastern Europe and Russia. 
• Individuals living or working in high-risk environments, such as prisons, homeless shelters, nursing homes, and healthcare facilities

When and Why Should You Get Tested for Tuberculosis (TB)?

The CDC recommends TB testing for individuals who:⁵

• Exhibit symptoms of TB
• Have been in close contact with someone diagnosed with TB
• Have lived or traveled to a country where TB is prevalent
• Work in healthcare, correctional facilities, or shelters
• Have a condition that compromises the immune system

For individuals at high risk, annual TB testing may be necessary to monitor potential exposure and prevent disease progression.⁵ You may also need to be tested for TB based on an employer’s requirements.⁶

What Tests Are Used to Detect Tuberculosis (TB)?

There are two types of TB tests available:

TB Blood Test (Interferon-Gamma Release Assay, IGRA)

• Measures the immune system’s response to TB bacteria in a blood sample⁶
• Requires only one visit for testing
• Recommended for individuals who received the TB vaccine, as it reduces the likelihood of false positives⁷
• Quest offers a TB blood test with no special preparation required

TB Skin Test (Mantoux Tuberculin Skin Test, TST)

• Involves injecting a small amount of tuberculin under the skin
• Requires a follow-up visit within 48–72 hours to check for a reaction
• May yield false positives in individuals who have received the TB vaccine⁶

Learn more about the differences between TB blood testing and skin testing.

How Do You Interpret TB Test Results?

It’s important to read and understand your TB test results. If your test is positive, that means you likely have been exposed to the bacterium, and your healthcare provider may order more tests to help make a diagnosis.⁶

TB Blood Test Results:

The QuantiFERON-TB Gold Plus will provide a positive or negative result. If positive for the bacteria, further testing is necessary to determine whether you have a latent TB infection (LTBI) or TB disease. This test can also provide negative results for those who have received the BCG TB vaccine or have been exposed to environmental mycobacteria. 

TB Skin Test Results:

The skin test will also provide a positive or negative result. If positive for the bacteria, further testing is necessary to determine whether you have a latent TB infection (LTBI) or TB disease. This test can also provide negative results for those who have received the BCG TB vaccine or have been exposed to environmental mycobacteria but has been known to yield false positives in individuals who have received the TB vaccine. NOTE: for the TB skin test you must have a healthcare professional read your results in a proper healthcare setting while TB blood test results will be delivered electronically in most cases.

If you have a positive test result, you and your healthcare provider will need to discuss a further testing and treatment plan. This may include a chest X-ray and taking a combination of medications over a period of several months.⁸ 

Why Choose Quest for Tuberculosis (TB) Testing?

Quest provides a convenient and reliable TB testing option with several key benefits:

• No doctor’s visit required—simply purchase testing online and visit a Quest location for sample collection.
• Fast results—get tested and receive your results quickly.
• Independent physician consultations—if your results indicate TB infection, you can discuss next steps with an independent physician at no additional cost.⁸

Buy your TB test

No doctor visit is required to buy your own lab test at questhealth.com. PWNHealth and its affiliates review your purchase to ensure it is medically appropriate before submitting the test order for processing. PWNHealth also reviews your test results and will contact you directly if they require prompt attention. Included in each purchase is the option to discuss your test results with an independent physician; however, you are also encouraged to speak with your primary healthcare provider.